Strange 5.1-BETA problem

[Tom Samplonius]

  I have two Dell Poweredge 6350s machines that have a strange problem
booting the 5.1-BETA disk 1 ISO, but work fine with 4.8.  During probing,
the display switches off.  It looks like the video adaptor ceases output.  
It is hard to see exactly where during the probing the display dies, but
it is likely at vga0 or nearby.

  These machines have 3GB of RAM, 4 x 550 Xeon, fxp ethernet, amr RAID,
and several unused ahc SCSI channels.  The video is on the motherboard,
and is supposed to be ATI Rage chipset.

Tom